The answer should be D hope this helps
<u>Answer:</u> The amount of energy absorbed by water is 5390 Calories
<u>Explanation:</u>
To calculate the amount of heat absorbed at normal boiling point, we use the equation:

where,
q = amount of heat absorbed = ?
m = mass of water = 10 grams
= latent heat of vaporization = 539 Cal/g
Putting values in above equation, we get:

Hence, the amount of energy absorbed by water is 5390 Calories
Because its only representing the most stable isotope of that element but its considered the atomic mass and not average atomic mass
Answer:
Ca₃(AsO₃)₂
Explanation:
Sodium arsenite, with the chemical formula Na₃AsO₃, is formed by the cation Na⁺ and the anion AsO₃³⁻. For the molecule to be neutral, 3 cations Na⁺ and 1 anion AsO₃³⁻ are required.
Calcium arsenite would be formed by the cation Ca²⁺ and the anion AsO₃³⁻. For the molecule to be neutral, we require 3 cations Ca²⁺ and 2 anions AsO₃³⁻. The resulting chemical formula is Ca₃(AsO₃)₂.